[ICS_Vortex]

Hi,

I was just wondering what the differences are between the CDI and Rectifier between the 2004 400ex model and the 2005 400ex model. The part numbers are different on both the CDI and Rectifier. The harness for a 2004 400ex where the CDI plugs in has a blank pin on one of the two connectors and the harness for a 2005 400ex where the CDI plugs in has no blank connectors. What is this newly added pin and where does it go? Also, I can't tell any difference between the rectifiers based on the harnesses because both harnesses have the same color wires going into the same places.
Essentially: I had an 04 400ex motor and bought an 05 400ex bottom end. I'm switching the harness over to 05 to run the 05 motor with the reverse and neutral indicators and need to know what the differences are between the CDI and Rectifiers. I know there's an extra pin in one of the two connectors on the 05 wiring harness for the CDI, but not sure what it controls, and I'm clueless on the Rectifier.

Thanks

 

[SlammedRanger]

My first guess would be reverse rev limit. It cuts spark at a really low rpm when in reverse.

 

[ICS_Vortex]

My first guess would be reverse rev limit. It cuts spark at a really low rpm when in reverse.

That would be for the CDI, correct?
Do you think that it would be alright to run the older CDI (assuming that the bike will run at all with the old one), just be smart about not going super fast in reverse? I don't have the bike assembled at the moment and it won't be reassembled for a little while at least, or I would try this.

Any idea about the rectifier differences? As far as I know, they only convert AC to DC power and also regulates voltage between other electrical components.

 

[SlammedRanger]

Cdi and probably the difference in the stator. Rectifier i would think is the same from any year. Couldnt see a difference necessary for that at all. The cdi boxes will not work. You have to have an 05+ for reverse to work. Without it reverse will shut the motor right off.

 

[ICS_Vortex]

Cdi and probably the difference in the stator. Rectifier i would think is the same from any year. Couldnt see a difference necessary for that at all. The cdi boxes will not work. You have to have an 05+ for reverse to work. Without it reverse will shut the motor right off.

Stator is identical from 99-14 according to part numbers. The rectifiers have different part numbers, but the wire colors on the harness are the same from 04-05 and match up spot-on, so I don't know what's different about them. I'm not too familiar with a lot of the newer stuff, but I know lots of the older Honda bike's electrical components would swap perfectly fine being different part numbers. I think Honda may have just wanted to sell the same part for a fraction more or less sometimes lol. Looks like I'll need to pick up a CDI from 05+ then.
On the terms of different part numbers and interchangeability, I also noticed that the kill/light switch between 04-05 had different part numbers, but have the exact same connector (I can't speak for the attached headlight connector because I'm using a modified headlight). Pretty sure it'll swap right over for my needs. I took a look at the wiring diagram and found out that the newer 05+ brake light (front and rear) tied into the kill/light switch assembly, so maybe that's a difference between those? If not, the difference may be the headlight connector, but as stated above, I can't really tell because my headlight is modified from a 1986 ATC 350x. I'm building something pretty cool :wink

Edit; also just compared wiring diagrams between 04-05 for the CDI extra pin and it definitely connects to the reverse switch and reverse indicator.

 

[SlammedRanger]

Well pre 05 didnt actually have a brake light. Just a running light. The main differences im aware of 04-05 are brake light. Front sprocket is 100% different. Reverse. Plastics. Subframe(mounting for rear brake light switch). Carbs are different. And the gearing internally is way different. Everything else is the same to my knowledge.

 

[ICS_Vortex]

Well pre 05 didnt actually have a brake light. Just a running light. The main differences im aware of 04-05 are brake light. Front sprocket is 100% different. Reverse. Plastics. Subframe(mounting for rear brake light switch). Carbs are different. And the gearing internally is way different. Everything else is the same to my knowledge.

What's different about the front sprocket? The 04 motor I have has the front sprocket and mounting hardware, but the 05 bottom end I just bought doesn't have a sprocket or the retaining hardware.

 

[SlammedRanger]

Sprocket itself is different. Not sure about mounting. But splines on the output shaft are different.

 

[ICS_Vortex]

Sprocket itself is different. Not sure about mounting. But splines on the output shaft are different.

Thanks for all your help. Looks like I'll definitely need to get a CDI, key switch, reverse/neutral indicator assembly, and the front sprocket and hardware and I believe I should have it ready to be swapped. Not gonna be running a brake light, so won't have to worry about getting the front/rear brake electric cables.

 

[SlammedRanger]

Your welcome! Always glad to help!

 

[ICS_Vortex]

Your welcome! Always glad to help!

Do you happen to know if the starters are interchangeable? Just got curious about them since the 05 bottom end I picked up didn't come with one. The part numbers are different between 04-05, but not sure what's different about them or if they're actually interchangeable. From what I can gather from a couple eBay listings, they both have the same number of teeth, rotate the same direction, and spline distance within 0.1mm tolerance (may just be the specific eBay listings I looked at).
P.S Sorry for getting off topic of my original post, just trying to get everything figured out for my build.

 

[SlammedRanger]

No worries. Its your thread. Do what you want in it. I dont know for sure about starters. I havent ever had one go bad on me. Sorry

 

[atvrider13]

I know this is an old old thread but I figured id add my experience to help anyone in the future. I had an 05 bottom end with a 99-2004 harness and cdi . Worked good , just didn’t have a reverse rev limit. Stator is the same also

 

[502tim]

I know this is an old old thread but I figured id add my experience to help anyone in the future. I had an 05 bottom end with a 99-2004 harness and cdi . Worked good , just didn’t have a reverse rev limit. Stator is the same also

Any other advice? I have a similar build going on 01 I’m swapping the bottom end with a 05 From what I understand the starter mounting is different along with sprocket. anything else you had a problem transferring? TIA